Knob and tube wiring, assessed and replaced.
Knob and tube wiring is common in older homes and a frequent reason insurers decline or won’t renew a policy. We assess it, replace it where needed and give you the ESA paperwork your insurer asks for.
Why insurers flag it
Knob and tube was used in homes built before about the 1950s. It isn’t illegal, but insurers see it as higher risk.
No ground
There’s no ground conductor, so modern grounded outlets and protection can’t be added without changes.
Aging insulation
After decades, the insulation can become brittle or damaged, especially where it’s been disturbed.
Not built for today’s loads
It was never designed for modern kitchens, electronics and heating loads, and it often has old splices added over the years.
- AssessmentWe look at the system, confirm what your insurer is concerned about and explain your options
- Written quoteClear scope and price before any work starts
- ESA permitFiled under our licence, ESA #7018850
- The workDone to the Ontario Electrical Safety Code
- Paperwork for your insurerESA Certificate of Acceptance once the work passes inspection
Insurer asking about something else? See all the electrical issues insurers commonly flag.
Knob and tube FAQ
No. The Ontario Electrical Safety Code isn’t retroactive, and ESA says knob and tube can be safe when it’s properly maintained by a licensed contractor. The issue is usually insurance: many insurers won’t cover it or require it replaced.
Not always. Some insurers want it fully removed, others accept an assessment or partial replacement. We’ll check what yours requires and what condition the wiring is in.
In most homes we fish new cable through walls and ceilings from the attic and basement, with small access openings where needed. We’ll explain what to expect for your house before we start.
Look in the basement or attic for single wires running through ceramic tubes or across ceramic knobs. If you’re not sure, send us a photo.
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“Excellent service / top-notch job completion. Was on time and completed the necessary work in a professional manner. Was very polite and great to work with. Would absolutely recommend.”
Have knob and tube wiring?
Send us a photo of the wiring in your basement or attic and your insurer’s letter if you have one. We’ll get back to you the same day.
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